Artificial tooth.



w. M. MUCHOW.

ARHFICIAL TOOTH.

APPLICATiON FILED SEPT. 17. I91 I.

1,267,42. Patented May 28, 1918.

FIG. 3.. FIG. 1 231a. If F1626:

WITNESSES: M/l/f/VTOR:

ATTORNEYS.

BY MM MW WILLIAM MARK MUGI-IOW, OF EVANSTON, ILLINOIS.

ARTIFICIAL TOOTH.

Specification of Letters Patent.

Patented May 28, 1918.

Application file'd'september 17, 1917. Serial No. 191,829.

To all whom it may concern Be it known that I, WILLIAM MARK MU- crrow, a citizen ofthe United States, and a resident of the city of Evanston, in the county of Cook and State of Illinois,'have invented a certain new and useful Improvement in Artificial Teeth; and I do hereby declare that the following description of my said invention, taken in connection with the accompanying sheet of drawing, forms a full, clear, and exact specification, which will enable others skilled in the art to which it appertains to make and use the same.v

My invention relates generally to im provements in artificial teeth; and it consists, essentially, in the novel and peculiar combination of parts and details of construc- "tion, as hereinafter first fully set forth and described and then pointed out in the claim.

The object of this invention is the production of artificial teeth which shall be exceedingly strong and durable, and which can be readily removed from their backing, when desired, or become necessary.

Artificial teeth employed in bridge-work, as heretofore made, are subjected to serious faults, for the reason that their fastening to the backing is weak; that owing to holes, channels, or grooves in the tooth, the same is very liable to crack or split, and become useless, entailing an expense to the person using these teeth, which expense is avoidable, and is intended to be overcome by the construction disclosed in this specification.

In the drawings forming a part of this specification, and which illustrate this i11- vention very fully, Figure 1 is a perspective view of a molar constructed in accordance with my invention. Fig. 2 is a side view of the same. Figs. 3 and 4- are perspective views of an incisor. Fig. 5 is a plane of the backing for these teeth, and Fig. 6 is an edge view of the same.

As shown in Figs. 1 to 4; inclusive, the backs of these teeth are considerably curved, as indicated at 13, and extending from these backs there are wedge-shaped projections 14, the larger end of which is adjacent the occlusal surface of the teeth, while the smaller end thereof terminates at, or near, the root of the tooth. The sides of this projecting wedge 14 are inclined to the face of the projection, as indicated at 15, which serves to tightly hold the tooth to the backing, and prevents rocking thereof.

The backing for these teeth, shown in Figs. 5 and 6, is a curved, generally gold, plate of even thickness throughout, and having approximately the contour of the back of the tooth in connection with which it is to be employed, which plate has its convex side provided with a Wedge-shaped groove 16, the sides of which are likewise inclined to the 'plane of the backing, and, said backing beingfformed from sheet metal, it follows that in the concaveface of this backing there is formed a tapering projection 17, corresponding in shape to the groove 16. This backing is soldered to the bridge, not shown,

and the tooth is inserted into the wedgeshaped groove of the backing by a rotative movement of the tooth, and cemented therein.

In view of the fact that the backing is soldered with its concave projection next to the bridge, it is apparent that at both sides of this projecting portion and the plate of the backing, there is quite a space between the plate and the bridge which in soldering the plate to the bridge, will be filled with solder, and, therefore, afford the strongest kind of fastening of the backing to the bridge.

As shown in Fig. 3, the projecting portion let on the back of the tooth merges into the said back some distance from the root thereof, while in Figs. 1 and 4, the same terminates at the margin of the root. Either construction is effective, the former construction being perhaps preferable, for obvious reasons.

Attention is now invited to the fact that the occlusal end of the tooth has the full area and strength of a natural tooth, and that the projection at the back of the tooth serves as a reinforcement thereto, so that this tooth is stronger than any other artificial tooth with which I am acquainted. There are in the wedge no pronounced rounded corners; angles thereof are acute, and the bearing-surfaces flat, thereby preventing rocking of the tooth. The tooth may be lowered without grinding the occlusal surface by reducing the sides of the wedge with an abrasive stone which can be readily done by the dentist. The backing can be readily produced in dies or other suitable instrument, by the dentist, and therefore, sold at a comparatively low price.

It will be noted that the pressure exerted on the tooth in biting or mastication, has a tendency to force -t-he tooth more tightly into, and increase the holding power of the tooth on its backing;- a

Attention is now directed to the fact that there are no shoulders on this tooth which" in biting or mastication, and the pressure thereby exerted-011 the tooth, will" finally cause the tooth to becomeloose and part from its backing, While in my novel construction, this pressure tends to more'securely tighten the tooth to its backing, which is animportant feature of my invention. j

Having; thus fully described this invention, I claim as new andv desire to secure to myself by Letters Patent of the United States The combination of an artificial tooth is fae1n'g,and a metallic backing for the same,

said'artificial tooth facing hayingrits back- Gopies ofthis patent may be obtained'for five cents each, by addressing the Commissioner of "Patents,'

surface pronouncedly concavedwithout an offset or shoulder therein, a concaved, tapering, projection-on the back of said tooth faccavo-convex contour, the convex face of said backing fittlng the concave surface of the backof said tooth facing, a hollow projection on the concave surface of the metallic backing said hollow projection being tapering. and affording in the convex face of the backin i a ta erin v roove constructed to engage; the concave projectiononthe back surface ofsa1d tooth faclng.

In testimony that I claim the foregoing-as my invention, I have hereunto set'my hand.

' WILLIAM 'MARK- MUCHOW.

Washington, D. 0; 

